Question
Question: If\(\int_{\sin x}^{1}t^{2}\) (f(t)) dt = (1 – sin x), then f\(\left( \frac{1}{\sqrt{3}} \right)\) is...
If∫sinx1t2 (f(t)) dt = (1 – sin x), then f(31) is –
A
31
B
31
C
3
D
3
Answer
3
Explanation
Solution
∫sinx1t2f(t)dt=1–sinx {given}
Differentiating both sides w.r.t. x using Newton
Leibnitz formula, we have
– sin2 x f (sin x) cos x = – cos x
Ž sin2 x f (sin x) cos x = cos x {cos x ¹ 0}
Ž f(sin x) = sin2x1, x ¹ (2n + 1)2π
\ f(x) = x21
Now, f(31) = 3